1. Field of the Invention
The present invention relates to a lens barrel and a camera system having the lens barrel.
2. Description of the Related Art
A photographer taking photographs by using a camera system may frequently focus on a subject located over a specific distance. For instance, at a baseball game, if a runner at first base attempts a steal while the photographer is taking a photograph by focusing on the batter, the photographer needs to instantly refocus the camera system on the runner on his way toward second base.
Japanese Laid Open Patent Publication No. H 6-43353 discloses a lens barrel having a function of resetting whenever necessary, to a focal point position stored in memory in advance in correspondence to a specific distance (hereafter referred to as a go-home function).
In a lens barrel that allows the focal length to be adjusted, the focal point position of the focus lens normally changes between the wide angle end and the telephoto end of the zoom lens. Thus, a photographer using such a lens barrel may not always be able to focus on the desired subject by performing a go-home operation.